The invention is in the field of painting, and in particular addresses high-pressure spray equipment that delivers airless sprayed paint under a pressure of 3000 pounds per square inch or more.
Sprayers of this type are trigger-operated somewhat similar to a typical gasoline pump, and for up-close work are used with no extensions or other attachments, being connected to the high-pressure paint delivery system through a flexible high-pressure hose.
When the painter is painting a ceiling or another structure in which it would be much more convenient to extend the spray head a distance away from the spray gun, typically a rigid wand is used. Such a wand is used when spraying in the corners of the ceiling and the walls of a room, as well as the portion of the walls.
If only a rigid wand is used, the painter is required to assume a strained and awkward position to operate the spray gun and deliver the spray to the ceiling. The gun is designed for more typical horizontal spraying operations, and it creates a problem for the painter to use it vertically.
Additionally, obviously a rigid wand will not always be able to delivery the paint spray evenly to an area that is hard to reach. For example, the corners between walls and ceilings of a room will receive the paint sprayed at an angle to both surfaces near their juncture suing a rigid rod extension.
To address this problem, spray gun extensions have been developed and marketed such as one represented in U.S. Pat. No. 3,915,382. This type of extension has a knuckle joint at the top which mounts the spray head, and may be adjusted and tightened to a particular angle to address a particular surface. This enables the painter to adjust the spray direction from parallel to the spray wand, to orthogonal to it, or even down toward the painter for covering the tops of surfaces.
However, jointed extensions of this type, although easing the burden on the painter considerably, are time consuming to adjust in that typically a wing nut must be loosened to disengage two radially striated interfaces to permit rotation of the spray head to a different angle. For a professional painter, adjusting this knuckle joint continuously all day long can become a real nuisance.
There is a need for a paint spray wand which is bendable with no memory so that it will retain the shape into which it is re-bent. This would permit one-handed adjustment by the painter, which could be done in seconds, and which could also orient the spray head in any rotational direction around the spray gun so that the spray gun itself could be held in the same orientation if desired.
Form-retaining conduits have been around for a long time and are put to many uses. They are commonly used in plumbing under sinks and toilets to connect water lines, and are also used in gas lines for appliances.
Sheathing of this type however is not meant to be repeatedly bent, as after several bends they will break. For example, U.S. Pat. No. 4,966,202 issued Oct. 30, 1990 discloses a bendable unit that will retain its shape, and confine a certain amount of pressure, but is not designed for very high pressures, and is not designed to be repeatedly bent.
What the painter needs is a paint spray wand having the combined characteristics of very high-pressure delivery capabilities, being as light weight as possible, and having a form-retaining length or lengths, with or without a rigid wand extension, which will hold the spray head very firmly in a desired position until the sheath length is re-bent.